The Laguna family hatchback was the first car to benefit when Renault lifted the wraps off a state-of-the-art new diesel engine.

A strong yet frugal 150bhp two litre unit - a product of the French producer's alliance with Nissan - had been revealed just five months earlier.

But Renault was keen to up the ante, and decided to take its oil-burning technology to new heights by fitting a more lusty 175bhp powerplant into the Laguna GT - the sport version of the company's popular mid-size model.

The result was, and remains, the most powerful two litre diesel in production, way up on the class average of 135bhp. In fact to match its output, other manufacturers are having to offer 2.5-litre units - which slurp more fuel.

With its hefty price tag this is not a car likely to attract hordes of private buyers, but it's one packed with credentials to lure the user-choosers of the fleet market.

For one thing, it's not only a fine model to drive on the motorway but the figures stack up too.

You can hit 62mph in a mere 8.4 seconds, experience enviable mid-range pulling power yet benefit from an average fuel return of 47 miles per gallon.

Handling and stability is improved courtesy of a re-designed chassis and cornering feels sharp thanks to stiffened suspension settings while the six-speed manual transmission is positive and shifts easily.

The GT looks the part too. Unashamedly sporty without being in your face, this car has the Laguna's elegant profile but with a discreet rear spoiler, stand-out alloy wheels, chrome detailing and body-hugging leather seats.

It doesn't look an especially large car, yet there's no denying the interior space. Head and legroom is excellent, even for tall passengers, the only one to suffer being a centre rear passenger whose seating position is perched.

And as for the taxman, the Laguna GT comfortably meets Euro IV emission rules, discharging only 159g/km of CO2.